The Americans with Disabilities Act (ADA) requires the installation of tactile warning surfaces in certain location to alert blind and other visually impaired pedestrians of potential hazards. Common locations for tactile warning surfaces include hazardous vehicular areas (e.g., intersections, street corners, and uncurbed transitions between pedestrian and vehicular areas) and areas having sudden drop-offs (e.g., train platforms and loading docks).
A tactile warning surface is typically formed by one or more tactile sidewalk tiles having a pattern of raised truncated domes and smaller pointed nubs. The tactile sidewalk tiles are placed over wet concrete so that an underside of the tactile sidewalk tile bonds to the concrete underlayer. The raised truncated domes and smaller pointed nubs provide tactile cues (e.g., through a sole of a shoe, through a sweeping cane, through a wheelchair wheel, or through a walker wheel) that alert the visually impaired pedestrian of the hazardous area ahead. The tactile sidewalk tile may also provide a visual cue (e.g., color contrast with the surrounding concrete) and/or an audio cue (e.g., sound attenuation caused by dissimilar materials used for the tactile sidewalk tile and the sidewalk).
While many intersections have sidewalks that meet a road surface at a single edge, for which a linear array of two or more rectangular (e.g., square) tactile tiles is appropriate, a rounded sidewalk corner, such as one that serves two perpendicular cross-walks or permits pedestrians to walk diagonally across an intersection, presents a situation for which an arcuate tactile warning surface that follows the inside of the rounded sidewalk corner would be appropriate. Conventional tactile sidewalk tiles typically have a rectilinear shape (e.g., square or rectangular). Many installers of tactile warning surfaces when faced with rounded sidewalk corners opt to arrange a plurality of rectangular tactile tiles along the curve of the sidewalk, but this undesirably leaves wedge-shaped gaps between the tactile tiles, which gaps are occupied by cementitious material or asphalt, and are free of any raised truncated domes. Such an arrangement also prevents the installer from pre-connecting a plurality of tactile tiles prior to installation, instead requiring that each tactile tile be installed independently.
Some have offered labor-intensive solutions to providing a more continuous arrangement of raised truncated domes along such rounded-corner sidewalks, involving providing a rectangular tactile tile with score lines that can be used to facilitate removal of portions of the rectangular tile until only a wedge-shaped region of the tactile tile remains. Such cut-down wedge-shaped tactile tiles are arranged between rectangular tactile tiles such that the array of rectangular and wedge-shaped tiles can then more closely mimic the rounded corner of the sidewalk. Therefore, to construct an arcuate tactile warning surface, it may be necessary to cut or otherwise modify one or more rectilinear tactile sidewalk tiles to form an arcuate shape. Re-shaping a tactile sidewalk tile in this manner is time-consuming and may require the use of a utility knife or even a motorized saw tool, particularly if the tactile sidewalk tile is made of metal or another strong material. In some cases, it may be necessary to cut the rectilinear tactile sidewalk tile at the installation site, without the assistance of measuring tools. As a result, it can be difficult to form an array of tactile sidewalk tiles with the proper curvature.